Multiphasic assessment of effects of design configuration on nutrient removal in storing multiple-pond constructed wetlands

[Display omitted] •High values of RE were obtained in SFWS CWs with shallow water depth.•High values of MRR and MRRV were obtained in deep-water EFTWs.•MRR and MRRV clearly revealed the removal performances of deep-water SMCWs.•Mixed planting improved plant cover in SMCWs with water depth less than 1.5 m.•EFTWs are suggested for the design of SMCWs with water depth more than 1.5 m. As an important technology for purifying and recycling agricultural wastewater, storing multiple-pond constructed wetlands (SMCWs) are widely used in the treatment of non-point source pollution. However, the influences of design configuration (surface area, volume, flow path, aspect ratio, water depth, percent vegetation cover and planting pattern) on pollution mitigation in SMCWs are still underexplored. To improve the sustainability of constructed wetlands, the removal performances of four groups of SMCWs were assessed through multiphasic analyses. The maximum removal efficiencies of nitrogen and phosphorus were 63.7% and 64.0%, respectively. Higher mass removal rates per square meter (MRR) and mass removal rates per cubic meter (MRRV) were observed in ecological floating treatment wetlands (EFTWs). Compared with RE, the interception performances of deep-water SMCWs were more clearly described by using MRR and MRRV. EFTWs with good plant configurations (mixed planting, 60–80% plant cover) were recommended in deep-water SMCWs (water depth > 1.5 m).